I only know last years Alliance splits
Alliance League:
Prem = Sunday Premier
Div 1 and 2 = Sunday Intermediate
Div 3 and 4 = Sunday Shield
Div 5 and 6 = Sunday Trophy
Div 7 = Sunday Vase
I think the county keep the Prem as the premier cup across all counties regardless of standard, so the LSL, Charnwood Prem teams will be in the Sunday Premier no matter what.